Optical system

ABSTRACT

An optical system is provided and includes a light-sensing element, a reflecting unit and a first driving assembly. The reflecting unit includes a reflecting surface, configured to receive an incident light and to reflect a reflecting light. The reflecting light travels into the light-sensing element. The first driving assembly is configured to control the reflecting unit to move along a first axis direction from a first position to a second position, so as to adjust a focus position of the reflecting light on the light-sensing element, wherein the reflecting surface in the first position is parallel to the reflecting surface in the second position, and a distance between a center of the reflecting unit in the first position and the center of the reflecting unit in the second position is not zero.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a Continuation of application Ser. No. 15/977,176,filed on May 11, 2018, which claims the benefit of U.S. ProvisionalApplication No. 62/505,420, filed May 12, 2017, and China PatentApplication No. 201810428101.7, filed May 7, 2018, the entirety of whichare incorporated by reference herein.

BACKGROUND OF THE DISCLOSURE Field of the Disclosure

The present disclosure relates to an optical system, and moreparticularly to an optical system that has a function of optical imagestabilization.

Description of the Related Art

As technology has progressed, many kinds of electronic devices such astablet computers and smartphones have begun to include the functionalityof digital photography or video recording. A user can take photos havingdifferent effects through the configuration of a lens system with a longfocal length. Electronic devices with the lens system with a long focallength have gradually become popular.

However, when a lens with a long focal length is disposed in theaforementioned electronic device, the thickness of the electronic devicemay increase, which is disadvantageous in the effort to miniaturize theelectronic device. Therefore, a reflecting member is generally disposedinside the lens system, and incident light is directed to alight-sensing element in the lens system through reflection. Based onthe configuration, the thickness of the electronic device can bereduced. However, when the electronic device is shaken, the position ofthe light-sensing element where the incident light reaches may shift toa position that is different from the predetermined position, resultingin unclear imaging by the lens system.

Therefore, how to design the structure of a lens system to prevent theproblem of an unclear image resulting from the shaking of the lenssystem is a topic nowadays that needs to be discussed and solved.

BRIEF SUMMARY OF THE DISCLOSURE

Accordingly, one objective of the present disclosure is to provide anoptical system having a plurality of driving assemblies, so as to solvethe above problems.

According to some embodiments of the disclosure, an optical systemincludes a light-sensing element, at least one optical lens, areflecting unit and a first driving assembly. The reflecting unitincludes a reflecting surface, configured to receive an incident lightand to reflect a reflecting light. The reflecting light is projectedinto the light-sensing element through the optical lens. The firstdriving assembly is configured to control the reflecting unit to movealong a first axis direction, so as to adjust a focus position of thereflecting light on the light-sensing element.

In some embodiments, the reflecting unit and the optical lens arearranged along a first direction, the incident light is emitted to thereflecting unit along a second direction, and a third direction isperpendicular to the first direction and the second direction, whereinthe first axis direction is not parallel to the third direction. In someembodiments, the first direction is substantially perpendicular to alight-sensing surface of the light-sensing element.

In some embodiments, the reflecting surface includes an arc structure.In some embodiments, a center of the arc structure corresponds to acenter of the incident light. In some embodiments, the reflectingsurface includes a radius, and the radius substantially ranges from 100to 1000 mm. In some embodiments, the reflecting surface further includesa flat surface, and the arc structure surrounds the flat surface. Insome embodiments, the arc structure is a convex structure or a concavestructure.

In some embodiments, the optical system further includes a seconddriving assembly, configured to drive the reflecting unit to rotatearound a second axis. In some embodiments, the optical system furtherincludes a third driving assembly, configured to drive the reflectingunit to rotate around a third axis.

The present disclosure provides an optical system with a long focallength that is installed in an electronic device for capturing images.The optical system can have a lens module, a reflecting module, alight-sensing element, and a plurality of driving assemblies. Thereflecting module includes a reflecting unit. The reflecting unit canreflect an external light to the lens module and then to thelight-sensing element, so as to generate a digital image. It should benoted that when the optical system is shaken, the plurality of drivingassemblies can control the reflecting unit to move along a first axisdirection, rotate around a second axis and/or rotate around a thirdaxis, to adjust the focus position of the reflecting light on thelight-sensing element, so as to achieve the purpose of optical imagestabilization. Therefore, the image quality of the light-sensing elementcan also be improved.

In some embodiments, the reflecting surface of the reflecting unit is aflat surface, and the driving assemblies can only control the reflectingunit to move along the first axis direction, so as to achieve thepurpose of compensating for the focus position. In addition, in someembodiments, the reflecting surface of the reflecting unit can furtherinclude an arc structure. Based on the design of the arc structure, thefocus position of the light which is reflected by the periphery of thereflecting surface onto the light-sensing element can be more accurate.

Additional features and advantages of the disclosure will be set forthin the description which follows, and, in part, will be obvious from thedescription, or can be learned by practice of the principles disclosedherein. The features and advantages of the disclosure can be realizedand obtained by means of the instruments and combinations pointed out inthe appended claims. These and other features of the disclosure willbecome more fully apparent from the following description and appendedclaims, or can be learned by the practice of the principles set forthherein.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a schematic diagram of an optical system installed on aportable electronic device according to an embodiment of the presentdisclosure.

FIG. 2 shows a schematic diagram of the optical system according to theembodiment of the present disclosure.

FIG. 3 shows an exploded diagram of a reflecting module according to theembodiment of the present disclosure.

FIG. 4 shows a partial structural diagram of the reflecting moduleaccording to the embodiment of the present disclosure.

FIG. 5 shows a schematic diagram of the reflecting module in anotherview according to the embodiment of the present disclosure.

FIG. 6 shows a partial structural diagram of the reflecting module inanother view according to the embodiment of the present disclosure.

FIG. 7A to FIG. 7C show diagrams illustrating that the optical system isin different states according to the embodiment of the presentdisclosure.

FIG. 8 shows a schematic side view of a reflecting unit according toanother embodiment of the present disclosure.

FIG. 9A to FIG. 9C show diagrams of an optical system in differentstates according to another embodiment of the present disclosure.

FIG. 10 shows a schematic side view of a reflecting unit according toanother embodiment of the present disclosure.

DETAILED DESCRIPTION OF THE ILLUSTRATIVE EMBODIMENTS

In the following detailed description, for the purposes of explanation,numerous specific details and embodiments are set forth in order toprovide a thorough understanding of the present disclosure. The specificelements and configurations described in the following detaileddescription are set forth in order to clearly describe the presentdisclosure. It will be apparent, however, that the exemplary embodimentsset forth herein are used merely for the purpose of illustration, andthe inventive concept may be embodied in various forms without beinglimited to those exemplary embodiments. In addition, the drawings ofdifferent embodiments may use like and/or corresponding numerals todenote like and/or corresponding elements in order to clearly describethe present disclosure. However, the use of like and/or correspondingnumerals in the drawings of different embodiments does not suggest anycorrelation between different embodiments. The directional terms, suchas “up”, “down”, “left”, “right”, “front” or “rear”, are referencedirections for accompanying drawings. Therefore, using the directionalterms is for description instead of limiting the disclosure.

In this specification, relative expressions are used. For example,“lower”, “bottom”, “higher” or “top” are used to describe the positionof one element relative to another. It should be appreciated that if adevice is flipped upside down, an element at a “lower” side will becomean element at a “higher” side.

The terms “about” and “substantially” typically mean+/−20% of the statedvalue, more typically +/−10% of the stated value and even more typically+/−5% of the stated value. The stated value of the present disclosure isan approximate value. When there is no specific description, the statedvalue includes the meaning of “about” or “substantially”.

Please refer to FIG. 1, which shows a schematic diagram of an opticalsystem 100 installed on a portable electronic device 50 according to anembodiment of the present disclosure. The portable electronic device 50can be any kind of portable electronic devices or handheld device, suchas a personal digital assistant (PDA), a smartphone, a tablet, a mobilephone, a mobile Internet device (MID), a notebook computer, a carcomputer, a digital camera, a digital media player, a gaming device orany other type of mobile computing device. However, it will beunderstood by a person skilled in the art that the present disclosure isnot limited to those devices. In this embodiment, the optical system 100can be a camera system with a long focal length and can provide a betterimage effect of a photo for a user. Light is emitted into the opticalsystem 100 through an opening 52, so as to generate one or severaldigital images.

Please refer to FIG. 2, which shows a schematic diagram of the opticalsystem 100 according to the embodiment of the present disclosure. Asshown in FIG. 2, the optical system 100 can include a lens module 200, areflecting module 300 and a light-sensing element 400. In addition, theoptical system 100 can further include a casing (not shown in thefigures), disposed in the portable electronic device 50 shown in FIG. 1,and the lens module 200, the reflecting module 300 and the light-sensingelement 400 are disposed in the casing. Specifically, the lens module200, the reflecting module 300, and the light-sensing element 400 arearranged along a first direction. For example, they are arranged alongthe Y-axis direction in FIG. 2. Furthermore, as shown in FIG. 2, thelens module 200 includes at least one optical lens (such as an opticallens 202), and the reflecting module 300 include a reflecting unit 302(such as a reflecting mirror). Therefore, the reflecting unit 302 andthe optical lens 202 are arranged along the first direction (forexample, along the Y-axis direction) as well.

As shown in FIG. 1 and FIG. 2, an external incident light IL is emittedalong a second direction (such as along the Z-axis direction) into thecasing through the opening 52 of the portable electronic device 50 andthen into reflecting unit 302. A third direction (such as the X-axisdirection) is perpendicular to the first direction (the Y-axisdirection) and the second direction (the Z-axis direction). In thisembodiment, the reflecting unit 302 can have a reflecting surface 3021,which is configured to receive the incident light IL emitted along thesecond direction (the Z-axis direction) and to reflect a reflectinglight RL. Then the reflecting light RL is projected along the firstdirection (the Y-axis direction) into the lens module 200. In thisembodiment, the lens module 200 in FIG. 2 only shows one optical lens202, but it is not limited to this embodiment. For example, the lensmodule 200 can include a plurality of optical lenses therein. When thereflecting light RL is projected into the lens module 200, the opticallens 202 of the lens module 200 is configured to guide the reflectinglight RL to the light-sensing element 400, and the light-sensing element400 generates an electronic signal after receiving the reflecting lightRL. The electronic signal is transmitted to the a processor (not shownin the figures) of the portable electronic device 50, so as to generatea digital image.

In addition, it should be noted that, as shown in FIG. 2, thelight-sensing element 400 has a light-sensing surface 402, and the firstdirection is substantially perpendicular to the light-sensing surface402. That is, the reflecting light RL is also substantiallyperpendicular to the light-sensing surface 402.

Please refer to FIG. 3, which shows an exploded diagram of a reflectingmodule 300 according to the embodiment of the present disclosure. Asshown in the figure, the reflecting module 300 includes a reflectingunit 302, an outer frame 304, a first elastic member 306, an opticalelement holder 308, a supporting base 310, a base 312, a plurality ofsecond elastic members 314, a first driving assembly DA1, a seconddriving assembly DA2, and a third driving assembly DA3. In thisembodiment, when the portable electronic device 50 is shaken, the firstdriving assembly DA1, the second driving assembly DA2, and the thirddriving assembly DA3 can be configured to drive the reflecting unit 302to move or rotate, so that the reflecting light RL in FIG. 2 can bestably reflected to the lens module 200 and the light-sensing element400, so as to achieve the purpose of optical image stabilization. Inaddition, in this embodiment, the first elastic member 306 may be aspring sheet which includes a central portion 3061, a side portion 3062and a side portion 3063. The central portion 3061 is connected to theside portion 3062 and the side portion 3063, and the central portion3061 can be rotated relative to the side portion 3062 and the sideportion 3063.

In this embodiment, the supporting base 310 includes a first housing3101 and a second housing 3103. The first housing 3101 is fixedlyconnected to the second housing 3103, such as being fixed to each otherwith a glue material. In addition, the third driving assembly DA3 caninclude two third driving coils CL31 and CL32 which are disposed betweenthe first housing 3101 and the second housing 3103. In addition, asshown in FIG. 3, the first housing 3101 includes a central groove 3105and two side walls 3107. The central groove 3105 is formed between thetwo side walls 3107, and the central groove 3105 is configured toaccommodate the optical element holder 308 and the second drivingassembly DA2.

Please refer to FIG. 3 and FIG. 4. FIG. 4 shows a partial structuraldiagram of the reflecting module 300 according to the embodiment of thepresent disclosure. In this embodiment, the reflecting unit 302 is anoptical reflecting mirror which is fixedly connected to the opticalelement holder 308 through the central portion 3061 of the first elasticmember 306, and the side portion 3062 and the side portion 3063 of thefirst elastic member 306 are respectively fixedly connected to the twoside walls 3107 of the first housing 3101. Therefore, the reflectingunit 302 and the optical element holder 308 are suspended in the centralgroove 3105 of the first housing 3101 by the first elastic member 306.As shown in FIG. 3, the third driving assembly DA3 further includes apair of third magnetic elements MG31 and a pair of third magneticelements MG32. The two pairs of third magnetic elements MG31 and MG32are respectively fixedly disposed on opposite sides of the opticalelement holder 308. In addition, the second driving assembly DA2 caninclude a second driving coil CL2 and a second magnetic element MG2. Thesecond driving coil CL2 is disposed on an inner surface of the centralgroove 3105, and the second magnetic element MG2 is disposed on aposition of the optical element holder 308 corresponding to the seconddriving coil CL2.

Next, in this embodiment, the outer frame 304 sheaths on the firsthousing 3101 of the supporting base 310, and the outer frame 304 canhave four protruding portions 3041 which are protruded along the X-axisdirection. Thus, the base 312 can be connected to the four protrudingportions 3041 of the outer frame 304 through the four second elasticmembers 314, as shown in FIG. 2. In addition, as shown in FIG. 3, thefirst driving assembly DA1 can include a first magnetic element MG11, afirst magnetic element MG12, a first magnetic element MG13, a firstdriving coil CL11, a first driving coil CL12 and a first driving coilCL13. In this embodiment, as shown in FIG. 3, the first magnetic elementMG11 is fixedly disposed on the first housing 3101 of the supportingbase 310 and faces the base 312, and the first driving coil CL11corresponding to the first magnetic element MG11 is disposed on the base312. In addition, the first magnetic element MG12 and the first magneticelement MG13 are fixedly disposed on two sides of the second housing3103, and the first driving coil CL12 and the first driving coil CL13are respectively disposed on two extending portions 3121 of the base312, facing the corresponding first magnetic element MG12 and the firstmagnetic element MG13.

As shown in FIG. 2 and FIG. 3, based on the above structuralconfiguration, the first driving assembly DA1 can control the supportingbase 310 to drive the reflecting unit 302 to move along a first axisdirection, so as to adjust a focus position of the reflecting light RLon the light-sensing element 400. For example, the first drivingassembly DA1 can control the supporting base 310 to move along the firstaxis direction, such as along the Y-axis direction or along the Z-axisdirection. However, it should be noted that the first axis direction isnot parallel to the third direction (the X-axis direction). In addition,it should be noted that positions of the magnetic elements and thedriving coils of the first driving assembly DA1, the second drivingassembly DA2 and the third driving assembly DA3 are not limited to thisembodiment. For example, the positions of the magnetic elements and thedriving coils can be interchanged. Furthermore, ways of driving thesupporting base 310 to move by the first driving assembly DA1 are notlimited to this embodiment. For example, the first driving assembly DA1can also be implemented by a stepping motor or piezoelectric drivingelements.

Please refer to FIG. 5, which shows a schematic diagram of thereflecting module 300 in another view according to the embodiment of thepresent disclosure. For clearly illustrating the first driving assemblyDA1, the base 312 is illustrated by dotted lines. In this embodiment,the magnetic pole direction of the first magnetic element MG11 is alongthe Y-axis direction. For example, the direction of the N-pole of thefirst magnetic element MG11 goes toward the Y-axis direction, and thedirection of the S-pole goes toward the −Y-axis direction. When thefirst driving coil CL11 is provided with electricity, an electromagneticdriving force Fy is generated by the first driving coil CL11 and thefirst magnetic element MG11 according to Lenz's law, so as to drive thereflecting unit 302 with the outer frame 304 to move along the Y-axisdirection relative to the base 312. Moreover, in this embodiment, thesecond elastic members 314 include a spiral structure, and when theouter frame 304 is moved along the Y-axis direction relative to the base312, the second elastic members 314 may be stretched or compressed.

In this embodiment, the magnetic pole directions of the first magneticelement MG12 and the first magnetic element MG13 are along the Z-axisdirection. When the first driving coil CL12 and the first driving coilCL13 are provided with electricity, the first driving coil CL12 and thefirst driving coil CL13 respectively act with the first magnetic elementMG12 and the first magnetic element MG13 to generate two electromagneticdriving forces Fz, so as to drive the supporting base 310 with thereflecting unit 302 to move along the Z-axis direction relative to thebase 312. Therefore, based on the configuration of the first drivingassembly DA1, the reflecting unit 302 can be driven to move relative tothe base 312 along the Y-axis direction or the Z-axis direction.

Please refer to FIG. 4 and FIG. 6. FIG. 6 shows a partial structuraldiagram of the reflecting module 300 in another view according to theembodiment of the present disclosure. As shown in FIG. 6, when thesecond driving coil CL2 of the second driving assembly DA2 is providedwith electricity, the second driving coil CL2 acts with the secondmagnetic element MG2 to generate an electromagnetic driving force Fzalong the Z-axis direction, so as to drive the optical element holder308, the reflecting unit 302, and the central portion 3061 of the firstelastic member 306 to rotate around a second axis Ax relative to theside portion 3062 and the side portion 3063. That is, theelectromagnetic driving force Fz can drive the reflecting unit 302 torotate around the second axis Ax relative to the supporting base 310(FIG. 4).

Similarly, as shown in FIG. 6, when the third driving coils CL31 andCL32 of the third driving assembly DA3 are provided with electricity(the currents received by the third driving coils CL31 and CL32 have thesame magnitude but opposite phases), the third driving coils CL31 andCL32 respectively act with the third magnetic elements MG31 and MG32 togenerate two electromagnetic driving forces Fv in opposite directions,so as to drive the optical element holder 308, the reflecting unit 302and the central portion 3061 of the first elastic member 306 to rotatearound a third axis Ay relative to the side portion 3062 and the sideportion 3063. That is, the electromagnetic driving forces Fv can drivethe reflecting unit 302 to rotate around the third axis Ay relative tothe holding base 310 (FIG. 4). It should be noted that the direction ofthe electromagnetic driving force Fv is substantially perpendicular tothe reflecting surface 3021 of the reflecting unit 302, that is, thedirection of the electromagnetic driving force Fv is parallel to thenormal vector of the reflecting surface 3021. In addition, directions ofthe second axis Ax and the third axis Ay are not parallel to thedirection of the electromagnetic driving force Fv. For example,directions of the second axis Ax and the third axis Ay are substantiallyperpendicular to the direction of the electromagnetic driving force Fv.

Please refer to FIG. 7A to FIG. 7C. FIG. 7A to FIG. 7C show diagramsillustrating that the optical system 100 is in different statesaccording to the embodiment of the present disclosure. In FIG. 7A, theoptical system 100 is parallel to a reference plane (such as beingparallel to the horizontal plane), and the reflecting light RL isreflected to a central position C (a focus position) of thelight-sensing element 400. FIG. 7B is a diagram of the optical system100 rotated clockwise at an angle relative to the horizontal plane. Asshown in FIG. 7B, because the optical system 100 is rotated at an angle(such as being rotated 5 degrees) relative to the horizontal plane, theposition of the reflecting light RL on the light-sensing element 400 maydeviate. As shown in FIG. 7B, the reflecting light RL is reflected to afirst position P1 on the light-sensing element 400.

In order to compensate for the deviated distance of the reflecting lightRL on the light-sensing element 400 (that is, the distance between thecentral position C and the first position P1), the first drivingassembly DA1 (FIG. 5) can drive the reflecting unit 302 to move alongthe direction (the −Y-axis direction) indicated by the arrow shown inFIG. 7B. Thus, the reflecting unit 302 can be moved from the position inFIG. 7B to the position in FIG. 7C. Therefore, as shown in FIG. 7C, theposition of the reflecting light RL on the light-sensing element 400returns from the first position P1 to the central position C, so as toachieve the purpose of optical image stabilization.

It should be noted that, in this embodiment, the reflecting surface 3021of the reflecting unit 302 is a flat surface, and it only needs to movethe reflecting unit 302 along the −Y-axis direction without rotating thereflecting unit 302 to achieve the purpose of compensation. In addition,based on the structural configuration of this embodiment, the reflectinglight RL which is reflected onto the light-sensing element 400 can stillhave good quality, so that the light-sensing element 400 can generate aclear image.

In this embodiment, when the optical system 100 is rotated clockwiserelative to the horizontal plane, the first driving assembly DA1 candrive the reflecting unit 302 to move along the −Y-axis direction, andtherefore the deviated distance of the reflecting light RL on thelight-sensing element 400 can be compensated for. Similarly, when theoptical system 100 is rotated counterclockwise relative to thehorizontal plane, the first driving assembly DA1 can drive thereflecting unit 302 to move along the Y-axis direction, and thereforethe deviated distance of the reflecting light RL on the light-sensingelement 400 can be compensated for. In this embodiment, the distance ofthe reflecting unit 302 compensated by the first driving assembly DA1may correspond to an angle between the optical system 100 and thehorizontal plane. For example, when the optical system 100 is rotatedclockwise 1 degree relative to the horizontal plane, the first drivingassembly DA1 drives the reflecting unit 302 to move with 125 μm alongthe −Y-axis direction, so as to achieve the purpose of compensating forthe deviated distance.

Please refer to FIG. 8, which shows a schematic side view of areflecting unit 302′ according to another embodiment of the presentdisclosure. In this embodiment, the reflecting unit 302′ includes areflecting surface 3022, and the reflecting surface 3022 includes an arcstructure. As shown in FIG. 8, in contrast to the reflecting unit 302 ofthe previous embodiment, the structure of the reflecting surface 3022 inthis embodiment can increase the angle between the reflecting light RLand the incident light IL. For example, when two parallel light beamsare emitted onto the reflecting surface 3022, two reflected light beamswith different reflecting angles are generated. As a result, the effectof compensation can be further improved.

Please refer to FIG. 9A to FIG. 9C, which show diagrams of an opticalsystem 100A in different states according to another embodiment of thepresent disclosure. In this embodiment, the optical system 100A includesa reflecting unit 302A. A reflecting surface 3023 of the reflecting unit302A includes an arc structure, and the center of the arc structurecorresponds to the center of an incident light ILL In addition, in thisembodiment, the arc structure of the reflecting surface 3023 is a convexstructure and is curved away from the lens module 200, but it is notlimited thereto. For example, in other embodiments, the arc structure ofthe reflecting surface 3023 can also be a concave structure and iscurved toward the lens module 200. Furthermore, in this embodiment, thearc structure can have a radius, and the radius ranges from about 100 to1000 mm.

In FIG. 9A, the optical system 100A is not shaken and is parallel to thehorizontal plane, and an incident light IL1 and an incident light IL2are emitted to the reflecting unit 302A along the Z-axis direction.Next, a reflecting light RL1 and a reflecting light RL2 are respectivelyreflected to a central position C1 and a side position C2 on thelight-sensing element 400. FIG. 9B is a diagram of the optical system100A after rotating counterclockwise at an angle relative to thehorizontal plane according to the embodiment of the present disclosure.As shown in FIG. 9B, because the optical system 100A is rotated at anangle (such as being rotated 5 degrees) relative to the horizontalplane, the positions of the reflecting light RL1 and the reflectinglight RL2 reflected on the light-sensing element 400 may deviate. Asshown in FIG. 9B, the reflecting light RL1 and the reflecting light RL2are respectively reflected to a second position P2 and a third positionP3 on the light-sensing element 400.

In order to compensate for the deviated distances of the reflectinglight RL1 and the reflecting light RL2 on the light-sensing element 400,the first driving assembly DA1 (FIG. 5) can drive the reflecting unit302A to move along the direction (the −Y-axis direction) indicated bythe arrow shown in FIG. 9B. Thus, the reflecting unit 302A can be movedfrom the position in the FIG. 9B to the position in FIG. 9C. Therefore,as shown in FIG. 9C, the position of the reflecting light RL1 on thelight-sensing element 400 returns from the second position P2 to thecentral position C1, and the position of the reflecting light RL2 on thelight-sensing element 400 returns from the third position P3 to the sideposition C2, so as to achieve the purpose of optical imagestabilization.

Similarly, in this embodiment, when the optical system 100A is rotatedclockwise relative to the horizontal plane, the first driving assemblyDA1 can drive the reflecting unit 302A to move along the Y-axisdirection, and the deviated distances of the reflecting light RL1 andthe reflecting light RL2 on the light-sensing element 400 can becompensated for.

Please refer to FIG. 10, which shows a schematic side view of areflecting unit 302B according to another embodiment of the presentdisclosure. As shown in FIG. 10, a reflecting surface 3025 of thereflecting unit 302B includes a flat surface PS and an arc structure CS,and the arc structure CS surrounds the flat surface PS. In thisembodiment, the arc structure CS has a radius, and the radius rangesfrom about 100 to 1000 mm. The reflecting unit 302B in this embodimentis similar to the reflecting unit 302A

In the embodiments of FIG. 9A and FIG. 10, based on the design of thereflecting surface having an arc structure, the focus position of thelight which is reflected by the periphery of the reflecting surface ontothe light-sensing element 400 can be more accurate. For example, thecompensation effect of the reflecting light RL2 in FIG. 9C can be moreaccurate.

In addition, in the other embodiments of the present disclosure, inorder to further improve the compensation result, the plurality ofdriving assemblies may further control the reflecting unit to move androtate together. For example, in some embodiments, the first drivingassembly DA1 and the second driving assembly DA2 can control thereflecting unit to move along the Y-axis direction and rotate around thesecond axis Ax together, so as to achieve the purpose of two-axiscompensation. In some embodiments, the first driving assembly DA1 cancontrol the reflecting unit to move along the Y-axis direction and theZ-axis direction together, so as to achieve the purpose of two-axiscompensation.

In addition, in some embodiments, the first driving assembly DA1 and thesecond driving assembly DA2 can control the reflecting unit to movealong the Y-axis direction, move along the Z-axis direction, and rotatearound the second axis Ax together, so as to achieve the purpose ofthree-axis compensation. In addition, in some embodiments, the firstdriving assembly DA1, the second driving assembly DA2, and the thirddriving assembly DA3 can control the reflecting unit to move along theY-axis direction, move along the Z-axis direction, rotate around thesecond axis Ax and rotate around the third axis Ay, so as to achieve thepurpose of four-axis compensation.

In conclusion, the present disclosure provides an optical system with along focal length that is installed in an electronic device forcapturing images. The optical system can have a lens module 200, areflecting module 300, a light-sensing element 400, and a plurality ofdriving assemblies. The reflecting module 300 includes a reflectingunit. The reflecting unit can reflect an external light to the lensmodule 200 and then to the light-sensing element 400, so as to generatea digital image. It should be noted that when the optical system isshaken, the plurality of driving assemblies can control the reflectingunit to move along a first axis direction, rotate around a second axisand/or rotate around a third axis, to adjust the focus position of thereflecting light on the light-sensing element 400, so as to achieve thepurpose of optical image stabilization. Therefore, the image quality ofthe light-sensing element 400 can also be improved.

In some embodiments, the reflecting surface of the reflecting unit is aflat surface, and the driving assemblies can only control the reflectingunit to move along the first axis direction, so as to achieve thepurpose of compensating for the focus position. In addition, in someembodiments, the reflecting surface of the reflecting unit can furtherinclude an arc structure. Based on the design of the arc structure, thefocus position of the light which is reflected by the periphery of thereflecting surface onto the light-sensing element 400 can be moreaccurate.

Although the embodiments and their advantages have been described indetail, it should be understood that various changes, substitutions, andalterations can be made herein without departing from the spirit andscope of the embodiments as defined by the appended claims. Moreover,the scope of the present application is not intended to be limited tothe particular embodiments of the process, machine, manufacture,composition of matter, means, methods, and steps described in thespecification. As one of ordinary skill in the art will readilyappreciate from the disclosure, processes, machines, manufacture,compositions of matter, means, methods, or steps, presently existing orlater to be developed, that perform substantially the same function orachieve substantially the same result as the corresponding embodimentsdescribed herein may be utilized according to the disclosure.Accordingly, the appended claims are intended to include within theirscope such processes, machines, manufacture, compositions of matter,means, methods, or steps. In addition, each claim constitutes a separateembodiment, and the combination of various claims and embodiments arewithin the scope of the disclosure.

What is claimed is:
 1. An optical system, comprising: a light-sensingelement; a reflecting unit, comprising a reflecting surface, wherein thereflecting surface is configured to receive an incident light and toreflect a reflecting light, and the reflecting light is projected intothe light-sensing element; and a first driving assembly, configured tocontrol the reflecting unit to move along a first axis direction from afirst position to a second position, so as to adjust a focus position ofthe reflecting light on the light-sensing element; wherein thereflecting surface in the first position is parallel to the reflectingsurface in the second position, and a distance between a center of thereflecting unit in the first position and the center of the reflectingunit in the second position is not zero.
 2. The optical system asclaimed in claim 1, wherein the reflecting unit and the light-sensingelement are arranged along a first direction, the incident light isemitted to the reflecting unit along a second direction, and a thirddirection is perpendicular to the first direction and the seconddirection, wherein the first axis direction is not parallel to the thirddirection.
 3. The optical system as claimed in claim 2, wherein thefirst direction is substantially perpendicular to a light-sensingsurface of the light-sensing element.
 4. The optical system as claimedin claim 1, wherein the reflecting surface includes an arc structure. 5.The optical system as claimed in claim 4, wherein a center of the arcstructure corresponds to a center of the incident light.
 6. The opticalsystem as claimed in claim 4, wherein the reflecting surface includes aradius, and the radius substantially ranges from 100 to 1000 mm.
 7. Theoptical system as claimed in claim 4, wherein the reflecting surfacefurther includes a flat surface, and the arc structure surrounds theflat surface.
 8. The optical system as claimed in claim 4, wherein thearc structure is a convex structure or a concave structure.
 9. Theoptical system as claimed in claim 1, further comprising a seconddriving assembly, configured to drive the reflecting unit to rotatearound a second axis.
 10. The optical system as claimed in claim 1,further comprising a third driving assembly, configured to drive thereflecting unit to rotate around a third axis.
 11. An optical system,comprising: a light-sensing element; a reflecting unit, comprising areflecting surface, wherein the reflecting surface is configured toreceive an incident light and to reflect a reflecting light, and thereflecting light is projected into the light-sensing element; a firstdriving assembly, configured to control the reflecting unit to movealong a first axis direction from a first position to a second position,so as to adjust a focus position of the reflecting light on thelight-sensing element; a second driving assembly, configured to drivethe reflecting unit to rotate around a second axis; and a third drivingassembly, configured to drive the reflecting unit to rotate around athird axis, wherein the reflecting surface in the first position isparallel to the reflecting surface in the second position, and adistance between a center of the reflecting unit in the first positionand the center of the reflecting unit in the second position is notzero.
 12. The optical system as claimed in claim 11, wherein thereflecting unit and the light-sensing element are arranged along a firstdirection, the incident light is emitted to the reflecting unit along asecond direction, and a third direction is perpendicular to the firstdirection and the second direction, wherein the first axis direction isnot parallel to the third direction.
 13. The optical system as claimedin claim 12, wherein the first direction is substantially perpendicularto a light-sensing surface of the light-sensing element.
 14. The opticalsystem as claimed in claim 11, wherein the reflecting surface includesan arc structure.
 15. A reflecting module, comprising: a base; asupporting base, is movably connected to the base; a reflecting unit,disposed on the supporting base, comprising a reflecting surface,wherein the reflecting surface is configured to receive an incidentlight and to reflect a reflecting light; a first driving assembly,configured to control the reflecting unit to move along a first axisdirection from a first position to a second position, wherein thereflecting surface in the first position is parallel to the reflectingsurface in the second position, and a distance between a center of thereflecting unit in the first position and the center of the reflectingunit in the second position is not zero.
 16. The reflecting module asclaimed in claim 15, wherein the reflecting surface includes an arcstructure.
 17. The reflecting module as claimed in claim 15, furthercomprising a first elastic member, connected to the reflecting unit,having a central portion and two side portions, and the central portionis connected to the two side portions, and the central portion isrotated relative to the two side portion.
 18. The reflecting module asclaimed in claim 15, wherein the first driving assembly comprises aplurality of magnetic elements and a plurality of driving coils, and oneof the magnetic elements is fixedly disposed on the first housing of thesupporting base, and one of the first driving coil corresponding to theone of magnetic element is disposed on the base.
 19. The reflectingmodule as claimed in claim 15, further comprising a second drivingassembly, configured to drive the reflecting unit to rotate around asecond axis.
 20. The reflecting module as claimed in claim 15, furthercomprising a third driving assembly, configured to drive the reflectingunit to rotate around a third axis.